pacman ... im sorry but think you should study a bit more.
cheating is using differnet muscles to asist the primary muscle group . e.g- back helping through 'sticking point' in bi-cep curl.
spotter = negative reps. - where they help wit the eccentric contraction.
altittude - refers to high above sea level .1968 mexio olympics no records broken for events lasting more than 2.30 mins. research conducted and due to partial pressure o2 / air density decreases. = less o2 to tissue , also higher attitude = solar radition and air doesnt hold asd much mostier therefore dyhration . however , general to best enhance athletes performance height = 1500-2000 meters. normally takes 2-3 weeks for benefits . 3 phase:
1. increase lung vent. due to o2 demand
2. erythropoietin - increase red blood :. heoglobin - ability more o2 to muscles
3. increased capilliarisation = oxidate enzymes.
- when coming back to sea level these benefits will last for a couple of days.
however negaitves - insensity decreaed coz less o2 .
hope this answers your question
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